It’s an astounding statistic that underscores the pervasive reach of Apple devices and the user engagement they facilitate.

Despite still being a relatively new communication medium, Apple’s iMessage, which was introduced as a new feature in iOS 5, has grown in popularity and user dependence with every passing month.

On Wednesday, during Apple’s earnings conference call, the Cupertino, California-based smartphone and tablet giant reported that more than two billion iMessages are now sent daily from 500 million Apple’s devices including iPhones, iPod touches, iPads, and even Macs running the latest OS X Mountain Lion operating system.

“The service, which replaces traditional text (SMS) and multimedia messages (MMS) for many iOS users, could have an impact on the larger ecosystem as it would save users up to $400 million daily in text messaging costs every day if those users paid a la carte for each message sent or received at today’s carrier rate of $0.20 per SMS or MMS,” observes tech writer Chuong Nguyen.

Messages that are sent via iMessage’s systems are delivered as data–and will count against your monthly data bucket–rather than as text messages.

Although the iMessage service has gone dark on occasion, prompting widespread user frustration in short bursts, Apple is routinely praised for its creation of iMessage. Some users even consider iMessage to be one of Apple’s best iOS features to date.